According to British newspaper The Sun, the 37 year-old even asked for the boots to include the label's trademark red soles.
A source told the publication: ''Forget Suri Cruise, this baby is going to be seriously cool.'
Posh Spice gave birth to her and husband David's first daughter by caesarean at Cedars-Sinai hospital in Los Angeles on July 10.
Victoria, who already has three boys - Brooklyn, 12, Romeo, eight, and Cruz, five - with David, 36, has apparently been secretly buying clothes for a baby girl for years.